1. Field of the Invention
The present invention relates to novel strains of lactic acid bacteria Lactobacillus sanfranciscencis having a property of producing an antibacterial agent exhibiting mold-proofing activity, a fermented seasoning liquid containing the bacteria which can be suitably added to food products to inhibit the generation of acidic smell, and a method for producing bread using the fermented seasoning liquid.
2. Description of the Related Art
Antibacterial agents produced by various microorganisms have been studied. Those antibacterial agents should be, when utilized in, for example, the food industry, harmless and less likely to degrade the flavor of the food products. Therefore, very limited number of antibacterial agents and microorganisms producing them are currently used in practice.
Among a variety of microorganisms, lactic acid bacteria have been conventionally contained in or added to various food products including dairy products such as yogurt since the antibacterial agents produced by them have been considered to be advantageous in that they are harmless and less likely to degrade the flavors of the food products. Examples of known antibacterial agents produced by lactic acid bacteria include organic acids such as lactic acid, hydrogen peroxide, and low molecular weight compounds such as diacetyl, as well as proteins including Nisin produced by Lactococcus lactis and diplococcin produced by Lactococcus cremoris, which have been used as yogurt and cheese starters.
Although those antibacterial agents can inhibit the growth of bacteria, however, they cannot disadvantageously inhibit the growth of, for example, mold or yeast. Mold may be a great menace to almost all kinds of food products since it could be the major cause for the rotting of foods. Therefore, it is important to inhibit the growth of mold in the food industry as much as possible.
Very few lactic acid bacteria have been reported which produce antibacterial agents that can inhibit the growth of mold, including Lactobacillus plantrum which produces, as antibacterial agents, organic acids such as phenyl lactic acid (see, for example, Paola Lavermicocca et al. Applied and Environmental Microbiology, September 2000, pp. 4084-4090, vol. 66, No. 9). However, those organic acids such as phenyl lactic acid may not have sufficient mold-proofing activity. Therefore, discovery or development of an antibacterial agent which can effectively inhibit the growth of, for example, mold and be harmless and less likely to degrade the flavor of food products as well as a novel lactic acid bacterium which produce the antibacterial agent are strongly demanded.
The object of the present invention is to provide: novel strains of lactic acid bacteria Lactobacillus sanfranciscencis having a property for producing an antibacterial agent which inhibits growth of mold (or exhibit mold-proofing activity); a fermented seasoning liquid containing any of the Lactobacillus sanfranciscencis strains which can be preferably used in food products such as bread dough, inhibit or mask acrid acidic acidic smell and/or sour taste without degrading the flavor of the food products, and exhibit antibacterial activities such as mold-proofing activity; and a method for efficient production of delicious bread that exhibits resistance to bacteria such as mold while inhibiting the generation of or masking acrid acidic acidic smell and/or sour taste.
The Lactobacillus sanfranciscencis strains according to the present invention have a property for producing an antibacterial agent which inhibits growth of mold.
A fermented seasoning liquid of Lactobacillus according to the present invention comprises Lactobacillus sanfranciscencis according to the present invention having a property for producing an antibacterial agent or agents that can inhibit the growth of mold.
A method for producing a bread according to the present invention uses a fermented seasoning liquid of Lactobacillus lactic acid bacterium having a property for producing an antibacterial agent which inhibits mold.